-LRB- CNN -RRB- -- A former security guard told CNN on Monday that he was unjustly fired after he took pictures of President Barack Obama 's motorcade during a visit to Atlanta in September .

Kenneth Tate worked for a private security firm when President Obama visited the Centers for Disease Control and Prevention on September 16 .

He told CNN 's Brooke Baldwin in an exclusive television interview that he stuck to his assigned duties and tried to take photos after he was done escorting President Obama .

Members of Congress were upset when the media reported last month that Tate had a .40 - caliber handgun while in an elevator with the President . That report , coupled with news of an incident in which a man jumped a fence and made it into the White House , led to the resignation of Secret Service Director Julia Pierson .

Tate said he was issued a weapon by his security firm on the morning of the President 's visit , but no one told him it was a violation of Secret Service protocol for him to carry a gun , he said .

Tate 's lawyer , Christopher Chestnut , said his client was fired unjustly for leaving his post .

`` He should never have lost his job for doing what he was supposed to do , '' Chestnut said . He added that Tate is not a felon , contrary to prior media reports .

Tate said he was supposed to take the President to two different floors of one of the CDC buildings .

`` Those tasks I carried out , '' he told CNN . He said he also was asked to escort some Secret Service agents to the roof and other locations

A federal official with knowledge of the investigation into the case said Tate was supposed to stay on the elevator and left to take pictures . The CDC asked for him to be reassigned for violating his post order , the official said .

Chestnut disagreed with the assertion that Tate violated his duties .

`` There was no assigned post . His post was for the entire building , '' the attorney told CNN .

The fired worker told Baldwin he only took photos when the detail was over and did not take any images while on the elevator , as had been reported .

The New York Times , which also interviewed Tate , reported that when he took pictures of the President 's limousine , the Secret Service became upset .

So did his bosses , Tate told the Times . They spoke with him to the side and then the Secret Service took him into a conference room .

`` I was upset . I 'm nervous because I 'm like , I do n't understand what 's going on , '' he told the Times , explaining to the newspaper that he had taken pictures of dignitaries before .

He said he deleted the photos and CDC officials took his badge .

It had been a great day up to then , Tate told CNN . Like the President , he is from Chicago and he had been very proud to work on Obama 's detail . They even shook hands when the President , his aides and their Secret Service detail got on the elevator .

Chestnut would n't be specific about what legal action they plan to pursue , saying only , `` We anticipate seeking justice for Mr. Tate . ''

The CDC did n't comment . CNN also reached out to Professional Security Corporation , the security company that employed Tate , but did n't hear immediately back .

Secret Service director testimony omits elevator incident with Obama at CDC

CNN 's Vishal Mapara and Mayra Cuevas contributed to this report .

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Fired security guard tells CNN he stuck to his assigned duties

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Kenneth Tate only went to take pictures when the detail was over , he says

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Federal official says CDC asked for Tate to be reassigned

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Tate says he carried a handgun that he was given , never took photos of President on elevator